Formation of anti-reflective alumina films on polymer substrates by the sol-gel process with hot water treatment

Al(2)O(3) films with a small roughness of less than 100 nm prepared through the sol-gel method have been found to show anti-reflective (AR) property in a wide wavelength region on polymer substrates such as poly(ethylene terephtalate) (PET), poly carbonate (PC), and poly(methyl methacrylate) (PMMA). The highest AR effects were obtained on PMMA substrates, the refractive index of which is similar to that of porous Al(2)O(3) gel films. The reflectance of PET, PC, and PMMA substrates coated with flowerlike Al(2)O(3) was less than 1.5, 1.0, and 0.8% in the visible light region, respectively. (c) 2006 Elsevier B.V. All rights reserved.